4-(trifluoromethoxy)aniline

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10/2019-08/2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

A stock solution was prepared to give the desired series of test concentrations. 100.9 mg of the test item were added to a 1 litre portion of dilution water and stirred for 0.5 h on a magnetic stirrer. The solution was apparently solved and was clear without visible particles (no Tyndall-effect was observed). The pH was measured to be 7.8.

Vehicle:

no

Details on test solutions:

To produce the different test item concentrations appropriate amounts of the stock solution were diluted with dilution water to a volume of 500 mL. 50 mL of the prepared solutions were taken per replicate and 0.5 mL of dilution water containing 5 daphnids was given to all replicates resulting in the final nominal concentrations. For each test item exposure concentration and for the control exposure 4 replicates were prepared.

Test organisms (species):

Daphnia magna

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

14.4 °dH (= 257 mg/L CaCO3)

Details on test conditions:

The main test was conducted as a static test with the test medium unchanged throughout the duration of the test.

During the test a temperature range of 18 - 22 °C was maintained in the test vessels, with a maximum temperature fluctuation of +/- 1 °C in each individual test.

The temperature, the pH and the oxygen values were measured at the beginning and end of the test. In order to avoid any potential impairment of the test system, an additional replicate was used at the beginning of the test. Measurements at the end of the test were performed using replicate 1 of the test concentrations and the control vessels.

Reference substance (positive control):

yes

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

7.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.67 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Validity criteria fulfilled:

yes

Conclusions:

The EC50 after 24 h was 7.3 mg/L. The EC50 after 48 h was 0.67 mg/L.

Executive summary:

TheDaphniawere exposed to a range of concentrations, nominally 0.018, 0.040, 0.088, 0.19, 0.43, 0.94, 2.1, 4.5 and 10 mg/L of4-trifluoromethoxyanilindissolved in dilution water.Auxiliaries used to prepare the test media was an magnetic stirrer.

Observations were made on the swimming ability and the percentage immobilised, respectively, after 24 and 48 hours of exposure. The following values were determined:

 

 

Time       EC 50      
[h]           [mg/L]     

 

24           7.3           

48                                                    0.67 

Description of key information

The EC50 after 24 h was 7.3 mg/L. The EC50 after 48 h was 0.67 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.67 mg/L